This application addressed broad Challenge Area (05) Comparative Effectiveness Research and specific Challenge Topic 05-MD-102*: Prevention of Chronic Diseases in Disparity Populations. The prevalence of pediatric obesity has tripled in the past three decades and inner-city minority children have been disproportionately affected, with up to twice the prevalence of white children. These rates are even higher, up to 47%, in some low-income minority communities, such as the Bronx, New York (NY). Physical inactivity is one of the contributing factors to the growing national epidemic of childhood obesity. Schools provide an ideal setting for promoting physical activity. However, many schools in inner-city communities, such as the Bronx, do not have facilities for physical education (PE). In addition, growing pressures to improve academic achievement in these schools reduce the opportunities for physical activity. To address these issues, we developed the "Moving Smart" audio CD, an innovative, short-burst, 10-minute, education-focused aerobic activity led by teachers in their classrooms. The overall goal of this research is to assess the effectiveness of the "Moving Smart" intervention on physical activity levels of inner-city, minority children attending Kindergarten through 3rd grade. To achieve this goal, we will conduct a cluster-randomized wait-listed controlled trial of 16,000 students (ages 4-9 years) attending 16 resource-poor elementary schools in the Bronx. The specific aims are: Primary Aim - To determine the effectiveness of the "Moving Smart" intervention on physical activity levels of intervention students as compared to wait-listed controls;Secondary Aims - 1) To determine the impact of "Moving Smart" on student fitness levels;2) To elicit the relationship between teacher adherence to "Moving Smart" and student physical activity levels during- and one-year post-intervention period. Students in 8 intervention schools will receive "Moving Smart" lessons, 6-times daily, for 10-minutes each time, in addition to regular PE classes during Year 1 of the project. Students in 8 wait-listed control schools will receive regular PE only during Year 1 and will be offered "Moving Smart" during Year 2 of the project. A pedometer, an objective measure of physical activity in children, will be used to determine mean number of steps students from both groups take during school hours for 5 consecutive days at baseline, and every 3 months during the 2-year study period. We will assess body mass index and fitness at baseline and annually. Teacher adherence to "Moving Smart" lessons, uploaded to each classroom's computer, will be measured objectively by computer software that will provide a log of date, time and number of "Moving Smart" lessons used daily. Proposed intervention draws elements from the Social Ecological Model. We will collect data on potential intervening variables and mediators of intervention effect. Through innovative methods and existing collaborations among established researchers, New York City Department of Education and local schools, this project is poised to provide a new and sustainable paradigm for childhood obesity prevention in resource-poor inner-city schools. 7. Project Narrative High prevalence of childhood obesity among inner-city, minority children represents a major public health concern with the potential for future health risks and growing burdens on the healthcare system. Although the World Health Organization identified promotion of physical activity in schools as an essential strategy to prevent childhood obesity, many schools in low-income communities, such as the Bronx, New York, lack facilities to provide daily physical activity as recommended by the government and clinical guidelines. This proposal will evaluate "Moving Smart", an in-classroom, education-focused physical activity intervention that may revolutionize the current school policy on physical activity and serve as a model for other obesity prevention school-based programs nationwide.